Final movie to feature Robin Williams in an on-screen role. His last movie, Absolutely Anything (2015), would feature only his voice.
This movie is dedicated to the loving memories of Mickey Rooney and Robin Williams, who appeared in the movie, but died before its release.
Plans for a spin-off featuring Jedediah and Octavius were canceled after Robin Williams died.
(at around 1h 11 mins) Ben Stiller's children made cameo appearances in the film, as the children staring at Larry and the gang, when they were sitting on the bus.
(at around 1h 11 mins) The X2: X-Men United (2003) theme is heard when Hugh Jackman (playing himself) poses as Wolverine.
(at around 22 mins) In Night at the Museum (2006), Teddy says the exhibits have been coming to life since the tablet of Ahkmenrah arrived in 1952. In this movie, Cecil says the tablet arrived in New York City following the expedition to Egypt in 1938 (depicted at the start of this movie). In the first movie, Ahkmenrah says he spent some years in England at one of the universities, suggesting he was sent to England for many years before he arrived in New York City.
Old night guards Cecil (Dick Van Dyke), Reginald (Bill Cobbs), and Gus (Mickey Rooney) return from Night at the Museum (2006).
Ben Stiller, Owen Wilson, Robin Williams, Ricky Gervais, Steve Coogan, Patrick Gallagher, Rami Malek, Mizuo Peck, Crystal the Monkey, and Brad Garrett are the ten actors who appear in all three Night at the Museum movies.
Hugh Jackman made his acting debut as King Arthur in a production of Camelot, when he was just five-years-old.
Teddy is shown quoting fellow U.S. Presidents John F. Kennedy, George W. Bush, and Franklin D. Roosevelt. He also quotes William Shakespeare's Henry V.
At the Egypt exhibit in the British Museum, some of the "hieroglyphics" are actually Hebrew letters. There is an Aleph to the left of Sir Ben Kingsley and a Hay-Tet to the right of Ben Stiller.
Ahkmenrah's evil brother Kahmunrah is not mentioned in the third movie at all, making Ahkmenrah seem like an only child.
According to an article about Robin Williams, he suffered from memory loss so that he couldn't remember what his lines were, causing him to become upset.
Jake Cherry played Nick Daley in Night at the Museum (2006) and Night at the Museum: Battle of the Smithsonian (2009). Here, he is played by Skyler Gisondo.
The cast includes three Oscar winners: Robin Williams, Sir Ben Kingsley, and Rami Malek and two Oscar nominees: Mickey Rooney, and Steve Coogan.
Dan Stevens (Sir Lancelot) and Hugh Jackman (King Arthur) have played X-Men. Jackman as Wolverine, Stevens as Legion.
Second time Skyler Gisondo took over a role first played by someone else. He was in the t.v. show Psych (2006) for the last couple of seasons and was the fourth boy to play the role of a young Shawn Spencer.
(at around 55 mins) Sir Ben Kingsley's character, an Egyptian pharaoh, says that he used to own forty thousand Jewish slaves when Larry (Ben Stiller) mentions he is Jewish. Kingsley's previous movie was Exodus: Gods and Kings (2014), in which he played a Jewish slave.
The triceratops skeleton is named Trixie, likely after the triceratops figure in Toy Story 3 (2010).
The musical score in the beginning of the movie resembles the song "Moondance". This is fitting as the moon's light is part of the plot and both the song's lyrics and the movie share themes of the night.
Anjali Jay (Shepseheret, Ahkmenrah's mother) is only six years older than Rami Malek (Ahkmenrah).
(at around 55 mins) Ben Stiller's character is half Irish and half Jewish, as Stiller is in real-life.
This is the fourth movie directed by Shawn Levy to feature Owen Wilson. The others are Night at the Museum (2006), Night at the Museum: Battle of the Smithsonian (2009), and The Internship (2013).
Dan Stevens (Sir Lancelot) and Hugh Jackman (King Arthur) played roles in live-action adaptations of Beauty and the Beast (1991). Jackman starred as Gaston in a stage production, and Stevens was in Beauty and the Beast (2017).
(at around 45 mins) The line "People Are Strange" comes from a popular song by The Doors, whose lead singer Jim Morrison loved history and magic.
The making and authorized distribution of this movie supported over fifteen thousand jobs and involved hundreds of thousands of work hours.
(at around 5 mins) Larry says that Dexter the monkey has "got a Chippendale thing going on". Ben Stiller is set to star in Chippendales.
This is the only movie in the trilogy to not be released three years later, and not to show the full opening credits at the beginning.